Systematic Review: 1.1 Quantitative Data Synthesis

Synthesis - Step-by-step

Step 1 synthesis

Quantitative Data Synthesis

In a quantitative systematic review, which explores similar studies (for example multiple studies that examine the effect

of cocoa on cholesterol levels), data will be processed through a meta-analysis. During meta-analysis, data from different studies are weighted depending on their sample size and relevant criteria, and evaluated to determine the cumulative outcome (e.g. whether recent research supports the use of cocoa to lower cholesterol). The results of a meta-analysis are most frequently represented in a Forest plot.



Example of Forest Plot

   Cochrane Collaboration: RevMan
  Joanna Briggs Institute: SUMARI
  OpenMeta[Analyst]completely open-source, cross-platform software for advanced meta-analysis
  OpenMEE open-source, cross-platform software for ecological & evolutionary meta-analysis
  Constructing a Forest plot in Microsoft Excel.
  A practical guide to interpreting and understanding meta-analysis graphs.
  How to interpret a Forest Plot

Additional resources



Cooper, H., Hedges, Larry V, & Valentine, Jeff C. (2009). The handbook of research synthesis and meta-analysis (2nd ed.). New York: Russell Sage Foundation.  (open access)

McKenzie, J., Beller, E., & Forbes, A. (2016). Introduction to systematic reviews and meta‐analysis. Respirology, 21(4), 626-637.

Wong, G., Greenhalgh, T., Westhorp, G., Buckingham, J., & Pawson, R. (2013). RAMESES publication standards: realist syntheses. BMC Medicine, 11(1), 1-14.  (open access)